Vibration generating apparatus

Abstract

A vibration generating apparatus including a support body having a first center axis, a first spherical joint element provided at a forward end of the support body and having the center of a sphere located on the first center axis, a vibrating body having a second center axis passing through the sphere center, a second spherical joint element provided on the vibrating body and concentric complementary with the first spherical joint element to cooperate therewith to allow the vibrating body to be supported on the support member for universal movement, a rotary shaft coaxially rotatably supported within the vibrating body, a pair of eccentric weights mounted on the rotary shaft with a phase deviation of 180 degrees and in a manner symmetrical with respect to the sphere center, and a drive motor connected to the rotary shaft for driving same for rotation whereby the pair of eccentric weights are rotated about the second center axis to cause the vibrating body to move in conical motion vibration such that the second center axis describes a circular cone having a vertex located at the sphere center about the first center axis.

What is claimed is: 
     
       1. A vibration generating apparatus comprising: a support body having a first center axis;   a first spherical joint element provided at a forward end of said support body and having the center of a sphere located on said first center axis;   a vibrating body having a second center axis passing through the sphere center of said first spherical joint element;   a second spherical joint element provided on said vibrating body, said second spherical joint element being concentric and complementary with the first spherical joint element and cooperating therewith to allow the vibrating body to be supported on the support body for universal movement;   a rotary shaft coaxially rotatably supported within the vibrating body;   a pair of eccentric weights mounted on the rotary shaft in such a manner that they deviate from each other in phase by 180 degrees and are symmetrical with respect to the sphere center of the first and second spherical joint elements; and   drive means connected to the rotary shaft for driving same for rotation whereby the pair of eccentric weights are rotated about the second center axis to cause the vibrating body to move in conical motion vibration such that the second center axis describes about the first center axis a circular cone having a vertex located at the sphere center of the first and second spherical joint elements.   
     
     
       2. A vibration generating apparatus as claimed in claim 1, wherein said first spherical joint element comprises a convex spherical surface portion and said second spherical joint element comprises a concave spherical surface portion in engagement with said convex spherical surface portion. 
     
     
       3. A vibration generating apparatus as claimed in claim 1, wherein said vibrating body includes a forward end portion of a conical shape, and a cylindrical portion extending rearwardly from said forward end portion into the interior of said support body, said rotary shaft being coaxially rotatably mounted in said cylindrical portion. 
     
     
       4. A vibration generating apparatus as claimed in claim 1, wherein said support body is in the form of a dual cylindrical structure having a first inner cylindrical portion and a first outer cylindrical portion open at their forward ends and closed at there rearward ends, said first spherical joint element being formed on a forward end of said first inner cylindrical portion and a portion of said vibrating body inserted between the first inner and outer cylindrical portions of the support body, and further comprising flexible seal means mounted between said portion of the vibrating body and the first outer cylindrical portion of the support body. 
     
     
       5. A vibration generating apparatus as claimed in claim 4, wherein said vibrating body includes a forward end portion of a conical shape and a dual cylindrical structure portion having a second inner cylindrical portion and a second outer cylindrical portion extending rearwardly from said conical forward end portion and open at their rearward ends, said second inner cylindrical portion inserted within said first inner cylindrical portion of said support body and said rotary shaft being coaxially rotatably supported in the second inner cylindrical portion, said second outer cylindrical portion inserted between the first inner and outer cylindrical portions of the support body and said second spherical joint element being formed on an inner side of the second outer cylindrical portion so as to engage with said first spherical joint element, and further comprising flexible seal means mounted between said first and second outer cylindrical portions. 
     
     
       6. A vibration generating apparatus as claimed in claim 5, wherein said drive means is mounted at a rearward end of the second inner cylindrical portion of the vibrating body. 
     
     
       7. A vibration generating apparatus as claimed in claim 1, wherein said vibrating body is constructed such that the center of gravity of the vibrating body is located on or rearward of the sphere center of the first and second spherical joint elements.